The heart in humans and animals is an internal organs that pumps blood and this function of the heart is conventionally reproduced by numerical analysis. In the numerical analysis of the heart, myocardial infarction, which causes changes over time at an arbitrary area of the heart, is simulated. When changes of such an area are to be viewed, a technique of extracting data corresponding to the area of the heart can be used (see, for example, Kitware, Inc., vtkMarchingContourFilter Class Reference.pdf, Sep. 27, 2010, retrieved Mar. 12, 2012: [URL]www.vtk.org/doc/release/5.6/html/a01103.html).
Nonetheless, with the technique above, an allowable range of an upper limit and a lower limit of physical values, which are elements of an arbitrary area and are for workrate and pressure, are specified as a myocardial infarcted area by a user. The allowable range of the physical values identifying the myocardial infarcted area varies according to patient and consequently, specification of an allowable range for a myocardial infarction is difficult. Such a problem is not limited to the heart and is similar for other internal organs as well as other disorders other than myocardial infarctions.